1. Field of the Invention
The present invention generally relates to recording and, more particularly, to a recording apparatus provided with a line recording head.
2. Description of the Related Art
A line printer provided with a full-line type line recording head can print a large amount of data at high speed, and is mainly used for print on demand. Usually, a line printer is adapted to handle various sheet widths. However, printing data on a large number of sheets having a narrow width results in that nozzles located at a position corresponding to the sheet width have prominently high discharge frequencies, compared to the other regions. The frequently used nozzles, in particular, core units of the recording head such as heaters and piezoelectric elements are rapidly deteriorated, and the ink discharge accuracy thereof is reduced. As a result, the image quality is partially deteriorated, which causes image unevenness.
Japanese Patent Application Laid-Open No. 2005-169962 discusses the technique for alleviating intensive use of a certain nozzle. The recording apparatus discussed in Japanese Patent Application Laid-Open No. 2005-169962 includes two feeding trays respectively corresponding to two recording positions disposed offset from each other in the sheet width direction of a sheet. According to this recording apparatus, the nozzle usage frequency is distributed by switching the feeding tray to be used to switch the recording position.
However, the apparatus discussed in Japanese Patent Application Laid-Open No. 2005-169962 has the following problems.    (1) The recording positions respectively corresponding to the two feeding trays are predetermined and cannot be changed. Therefore, although the usage frequency is reduced by half, the deterioration of the nozzles at the predetermined recording positions still progresses faster than the other regions.    (2) The two feeding trays can only supply sheets of a predetermined same size, and partial deterioration of nozzles can be alleviated only when sheets of that size are used. This recording apparatus lacks flexibility for handling various sheet sizes.    (3) Even if the recording apparatus is configured to enable replacement of feeding trays having different sizes for handling various sheet sizes, in this case, a pair of two feeding trays is necessary for each of various sizes, and storage of the feeding trays while out of use should be prepared, which may cause another problem. Further, in this case, the recording apparatus should have a tray holding mechanism and a conveyance mechanism which can be used with the feeding trays of the various sizes. As a result, the recording apparatus becomes bulky and a complicated control becomes necessary.